Comparison of SPWM and SVM Based Neutral Point Clamped Inverter fed Induction Motor

Neutral point clamped multi-level inverter (NPCMLI) has a wide application prospect in high-voltage and adjustable speed drive systems due to its low stress on switching devices, low harmonic output, and simple structure. However, the problem of performance of induction motor needs to be solved when the Sinusoidal pulse width modulation (SPWM) is implemented on neutral point clamped inverter. In this paper, a space vector modulation (SVM) system is proposed for a three-level neutral-point-clamped (NPC) inverter with an induction motor as load. Consequently, the neutral-point potential unbalance, the dv/dt of output voltage and the switching loss are restrained effectively, and desirable dynamic and steady-state performances of induction machines can be obtained by SVM based NPC compare to the SPWM based inverter. Keywords: Neutral Point Clamped Inverter, Total Harmonic Distortion, Sinusoidal Pulse Width Modulation, Space Vector Modulation